Earth wobbles slowly like a spinning top, tracing a full circle about every 26,000 years. So the point in the sky our axis points to drifts over time. From about 3900 to 1800 BCE, the pole star was Thuban in the constellation Draco, not Polaris. The Great Pyramid was finished around 2560 BCE.
Truth label: Established. Strong evidence and broad agreement among experts.
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Polaris is still getting closer
Polaris will come nearest to the true north pole of the sky around the year 2100, then slowly drift away.
Vega's turn
Around 14,500 CE, the bright star Vega will be near the pole. Thuban will be the pole star again around 20,346 CE.
Learn
- Precession. This slow wobble of Earth's axis is called precession.
Test yourself
Roughly how long does one full wobble of Earth's axis take?
26,000 years. About 26,000 years for one full circle.
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